As for why Mst III and IV are not available for digital distribution, Cyan and Ubisoft are currently discussing transferring rights between Ubi (the publisher of 3 and 4) to Cyan, don't have the link right a quick Google should yield that. As Cyan is the franchise rights holder but not the developer of Myst 3 and 4 those 2 games must be in some sort of legal murkiness as to how profits are going to be split and that's why they have not been made available yet, a shame really.

I really wish they would complete whatever deals they need to do to release Myst III and IV to GOG/Steam. I'm working my way through Riven and really want to go through the series in order. I would rather not mess with the old physical copies.

As for why Mst III and IV are not available for digital distribution, Cyan and Ubisoft are currently discussing transferring rights between Ubi (the publisher of 3 and 4) to Cyan, don't have the link right a quick Google should yield that. As Cyan is the franchise rights holder but not the developer of Myst 3 and 4 those 2 games must be in some sort of legal murkiness as to how profits are going to be split and that's why they have not been made available yet, a shame really.

I have done a thorough Google search and have turned up with no such archive or credible evidence of what your saying. Can you please search for and provide a link to an article that backs your claim of Ubi talking to Cyan about transferring rights to those games?